1. Field of the Invention
This invention lies in the field of slip rings and brushes, for noise-free operation of sliding electrical contacts under low current operation.
More particularly, this invention relates to rotating electrical contacts such as used in the art of sonar signalling and display.
More particularly, this invention relates to a sonar sound ranging apparatus including a visual display disc which carries a glow tube for the purpose of producing a pulse of light on receipt of an electrical pulse generated by the returned sonar pulse in the water. The brushes and slip rings are required to carry the returned sonar pulse signal to the rotating disc, which carries the glow tube.
2. Description of the Prior Art
In the prior art there have been numerous sonar display units which utilize a rotating disc for timing the instant of transmission of a sonar pulse in the water at one point in the disc rotation, and creating a pulse of light at a second time delayed by the travel time of the sonar pulse, the position of the disc at the instant of receipt of the reflected sonar pulse being a measure of the travel time of the sonar pulse.
One of the major problems with this type of equipment, however, is the manner of getting the electrical return pulse signal to the glow tube mounted on the rotating disc. Troubles in the nature of corrosion of metal connectors, fatique of brushes, noise due to the low current transmission, etc. have been common to these designs.
It is the purpose of this invention to provide a design which is a major improvement over the existing designs.